carotid sinus syncope
Quick Summary
Carotid sinus syncope, also known as the tight-collar syndrome, is a medical condition characterized by a brief loss of consciousness due to impaired blood flow to the brain. Unlike ordinary fainting, it is not typically preceded by paleness, nausea, or sweating.1
The carotid sinus is a sensitive area in the carotid artery in the neck. Pressure on this area, from a tight collar, turning the head, swallowing, or shaving, can stimulate nerve endings. This stimulation causes the heart to slow down and blood vessels to dilate, leading to a drop in blood pressure and reduced blood flow to the brain. This can result in temporary unconsciousness. This type of syncope can also occur spontaneously.12
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Carotid sinus syncope, sometimes called the tight-collar syndrome, also causes brief unconsciousness from impaired blood flow to the brain. Unlike the ordinary faint, this syncope is not preceded by pallor, nausea, and sweating. (The carotid sinus is a widened portion of the carotid artery where…
Read MoreCarotid sinus syncope, sometimes called the tight-collar syndrome, also causes brief unconsciousness from impaired blood flow to the brain. Unlike the ordinary faint, this syncope is not preceded by pallor, nausea, and sweating. (The carotid sinus is a widened portion of the carotid artery where…
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human nervous systemGlossopharyngeal nerve (CN IX or 9)…this is known as the carotid sinus reflex.
Read More…this is known as the carotid sinus reflex.
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